The garden is set in a steep, English ivy-covered hillside populated by mature oak trees.

Merten’s aim was to create a new space — patio, deck and slope — planting with multilayered variations in size, color and pattern. He wanted plants that could also tolerate shade.

Because many rooms of the house look onto the garden and side yard, the design had be visually exciting from every angle.

“The views into the exterior from the house needed to draw attention and expand the movement of our eye outwards to be successful,” Merten says.

The black cement patio — which is used as an outdoor room of sorts — begins with a central nexus. From there, concentric rings extend outward. The space extends into the topography, allowing radiating forms to bend and twist.

The top portion of the garden has a seating area of crushed oyster shells.

The white cement blocks serve two functions: to act as retaining walls and to provide energizing and uniform building blocks that add an unexpected playfulness, subtly reinforcing the concentric pattern of the patio.

Plantings include tropical specimens such as Hedychium greenei, iris, calla lily, Persicaria and Viola odorata, as well as tree ferns, ginger and abutilon.

Merten, who heads Studio Green and brings 20 years of experience — some at famed Skidmore, Owings and Merrill in Chicago — says, “We design gardens that are unique and one of a kind.”